Carnivore repatriation and holarctic prey: narrowing the deficit in ecological effectiveness.

摘要: The continuing global decline of large carnivores has catalyzed great interest in reintroduction to restore populations and reestablish ecologically functional relationships. I used variation the distribution four Holarctic prey species their behavior as proxies investigate pace intensity by which responses are lost or reinvigorated carnivore repatriation. By simulating presence wolves (Canis lupus), tigers (Panthera tigris), brown bears (Ursus arctos) at 19 transcontinental sites, assayed three metrics performance areas with no terrestrial (the polar islands Greenland Svalbard), extant native (Eastern Siberian Shield, boreal Canada, Alaska); repatriated Yellowstone region Rocky Mountains). loss reestablishment changed ecological effectiveness systems (1) dampening immediate group benefits, diminishing awareness, flight reaction caribou (Rangifer tarandus) where predation was eliminated (2) reinstituting sensitivity elk (Cervus elaphus) moose (Alces alces) levels observed Asian when sympatric Alaskan wolves. Behavioral compensation reintroduced occurred within a single generation, but only vigilance bison (Bison bison) exceeded that wolf-exposed conspecifics from Canada. Beyond these overt prey, snow depth distance suitably vegetated habitat related heightened elk, respectively, sites carnivores. These findings insufficient determine whether similar patterns might apply other alien predators, they suggest presumed excessive vulnerability naive may be ill-founded. Although offers proxy evaluate effectiveness, challenge will understand how respond novel introduced predators.